Republican Officials Brace for Chaos at Convention

CLEVELAND — Republicans are bracing for the possibility of a drawn-out fight over Donald J. Trump’s nomination that could stretch into the convention next week, a spectacle party leaders are desperate to avoid.

As the party’s governing body convened in Cleveland on Wednesday for a series of organizational meetings, the possibility that the smoldering dissent over Mr. Trump could become a full-blown eruption on the convention floor was a top concern.

Party officials were working in overdrive behind the scenes to beat back two challenges. One would force a vote that could theoretically open up the convention to any candidate who wants to seek the nomination. A second, organized by supporters of gay rights, would strike the entire Republican platform, which is staunchly conservative in its treatment of sexuality, gender and religion.

Supporters of the platform overhaul said the Trump campaign and the Republican National Committee were pressuring them to back down.

The Republican national chairman, Reince Priebus, was blunt about the need for party leaders to support Mr. Trump and defeat Hillary Clinton — even if the reasoning he offered appeared to be less than a full-throated endorsement.

“If we don’t stick together as a party and stop her, then the only alternative is to get comfortable with the phrase President Hillary Clinton,” Mr. Priebus said in remarks to party leaders.

An extended and confrontational debate could reopen doubts about Mr. Trump’s candidacy and cast a shadow over what is supposed to be a triumphant moment of party unity.

“I think the R.N.C. is threatened by not wanting to open up anything on the convention floor, and the Trump campaign is threatened by the same thing,” said Rachel Hoff, a delegate from the District of Columbia who has signed the petition to force the reconsideration of the platform.

The petition had 37 signatures. But some signers have since backed off under pressure, raising doubts about whether the floor vote will occur.

“Why even have a convention then?” Ms. Hoff said, adding that the committee’s interference was stifling the voices of delegates. “They won’t let us do anything at the convention that isn’t part of their neat little script.”

The prospect of taking multiple votes with unknown outcomes and unforeseeable consequences is something Mr. Trump’s campaign and Mr. Priebus are intent on preventing. It could send what is ordinarily a carefully choreographed event — planned to conform neatly to the prime-time schedules of the television networks — into chaos.

The likelihood that Mr. Trump’s opponents could muster the support to deny him the nomination is remote. The biggest hazard Mr. Trump and the leaders of the Republican National Committee are trying to contain is how messy the process becomes — and how much damage he could sustain as a result.

Starting on Thursday morning, delegates will begin to answer those questions as they debate a series of proposals to change the party’s rules. Those proposed changes will probably include a provision that would allow delegates to vote their consciences, instead of voting in accordance with the outcomes of the primaries and caucuses in their states, as most state party rules require.

Only 28 votes are needed to send that proposal, which could turn the vote for the nomination into a free-for-all, out of the 112-member rules committee and onto the convention floor.

The provision, known as a “conscience clause” or an “unbinding” rule, does not appear to have enough support to pass. It would require a majority of delegates, 1,237, to approve it. And many, regardless of their feelings for Mr. Trump, are unwilling to undo the results of the primary process and nullify the votes of the 14 million people who cast ballots for Mr. Trump.

Committee members have been told to prepare for several days of meetings that could stretch into the weekend. And Mr. Priebus has stacked the committee with people who are loyal to him. But some of them do not know whether there will be enough votes to keep the proposals from reaching the convention floor and going to a ballot before all 2,472 delegates.

“I have no idea,” said Ron Kaufman, a chairman of the rules committee. There may or may not be rogue amendments that go to the floor and require a vote from the entire convention, he said. “It’s part of the process. And as long as the process is fair, open, honest and transparent, that’s all that matters.”

But the scenes that would unfold on national television are ones that the party and the Trump campaign would find most unwelcome: hostile delegates seizing the microphone to voice their displeasure with the party and its presumptive nominee.

“They clearly are concerned,” said Dane Waters, who is working with Delegates Unbound, a group trying to block Mr. Trump. “If there are people who are trying to stop the process from operating the way it should, that’s when chaos occurs.”

Correction:July 14, 2016

An earlier version of this article misstated the total number of delegates voting on proposals to reach the Republican convention’s floor. It is 2,472, not 2,475.

A version of this article appears in print on , Section A, Page 16 of the New York edition with the headline: Challenges to Party Platform Leave Republicans Bracing for Chaos at Convention. Order Reprints | Today’s Paper | Subscribe